The present disclosure relates to an image forming apparatus for transferring a toner image to a sheet.
An image forming apparatus for transferring a toner image to a sheet includes a transfer nip portion formed by a photoconductive drum forbearing a toner image and a transfer roller to which a transfer bias is applied. A toner image on the circumferential surface of the photoconductive drum is transferred to a surface of a sheet by the sheet passing through this transfer nip portion. A guide member for properly guiding a sheet toward the transfer nip portion is provided immediately upstream of the transfer nip portion in a sheet conveying direction. A main function of the guide member is to prevent so-called transfer scattering (scattering of toner occurring during transfer) which occurs because toner is preliminarily transferred onto a sheet due to a transfer bias in a pre-nip area immediately upstream of the transfer nip portion. To suppress transfer scattering, it is effective to guide a sheet toward the circumferential surface of the photoconductive drum in the pre-nip area. Thus, the guide member is arranged upstream of the transfer nip portion to enable sheet guidance.
In the guide member as described above, in order to moderate an impact or reduce a conveying load in passing thick paper such as postcards through the transfer nip portion, it is known to provide a cut portion in the form of a recess having a postcard size on a guide surface of the guide member. There is also a technology for suppressing the occurrence of image defects such as missing images by covering the cut portion with a sheet-like elastic member from above.
However, in the above configuration, the trailing end of a sheet may flap because of the elastic member when leaving an end edge of the elastic member. If such flapping of the sheet occurs in the pre-nip area, toner may scatter and a transferred image on the sheet may be blurred.